(a) Field of the Invention
This invention relates to an ophthalmic solution designed for and adapted to general use in the eyes of humans and domestic animals. More specifically, the patent invention relates to an ophthalmic solution which reduces swelling of the cornea.
(B) Description of the Prior Art
The only prior art use of tranexamic acid in ophthamology is the work reported in Acta Ophthalmologica (Kbh) vol. 55, pages 665-673 (1977) and Acta Ophthalmologica (Kbh) vol. 56, pages 121-126 (1978). In these papers it is reported that tranexamic acid when given orally to man is helpful in relieving the symptoms of bullous keratopathy subsequent to Fuchs endothelial dystrophy, as well as severely impeding post-surgical corneal edema often found after cataract surgery. Tranexamic acid has been used as an antifibrinolytic agent in man at dose levels up to 1 gram administered orally three times daily (total daily dose, 3 grams). It is not known whether the rate of uptake of the drug from the intestine allows the attainment of plasma levels as high as 25 .mu.g/kg, which is the theoretical maximum from a 1 gram oral dose.
Tranexamic acid, ##STR1## trans-4-(aminomethyl) cyclohexanecarboxylic acid (AMCHA) has been the subject of investigations and patents relating to its effect in suppressing the activity of plasmin in vivo. See for example, Merck's Index, 9th Edition, Merck and Co., publishers, Rahway, N.J., 1976, item 9259 on page 1230, U.S. Pat. Nos. 3,268,405, 3,574,721, 3,639,626 and 3,950,405. None of this prior art work suggested the use of tranexamic acid for reducing swelling of the cornea.